Open end ratcheting wrench



Jan. 9, 1951 G. T. LOGAN OPEN END RATCHETING WRENCH Filed Dec. 18, 1946H y R M m W N /Z M A m w e m? 6 B final Patented Jan. 9, 1951 UNITEDSTATES PATENT OFFICE OPEN END RATCHETING WRENCH George Logan, New-Hope,Pa. Application December 18, 1946, .SerialN0. 716,906

18 Claims; 1

This invention relates to open-end ratcheting wrenches, and particularlythe type intended for use with hexagonal nuts or bolt heads.

I have found that the wrenches heretofore available are not capable ofuse in many instances on the present day airplane and automotive vehiclebecause the installation renders the bolt or'nut' practicallyinaccessible. Not only is'the spaceavailable for turning a wrenchextremely limited, but the clearance necessary to engage the jaws ofa'wrencharound the nut or bolt head is likewiselimited, particularly onaircraft starters, generators, and the like;

The design of these parts prohibits the use of theordinary socket wrenchbecause the-bolts or studs are recessed in the starter housing and theare through which an ordinary open-end wrench can be turned in such alocation is so limited that the wrench" must be reversed'every time thenut is moved even an eighth of a turn orless. This condition alone hasresulted in a great loss of time in servicing aircraft engines, anoperation which under present conditions must be done with the greatestdispatch and efiiciency.

Furthermore, the ordinary open-end wrench having fixed jaws dependsentirely upon the shape of the nut or bolt head for its turning actionsince'it has no gripping function. If the nut becomes worn or isslightly undersize, such a Wrench is useless. My invention contemplatesa wrench having jaws which will grip the nut securely even thoughundersize or worn and in addition does not require removal andreversing.

In addition to the above advantages, I have found that manyinstallations where tubing is used; for example in the refrigerationindustry, require a special type of wrench to install the tube nuts.Such a wrench, when used on an assembly line in the mass production ofrefrigeration units or similar devices, must be capable of beinginserted quickly around the tube nut and of quickly tightening the nutwithout slipping. By shortening such an operation only a few seconds oneach installation, increased productive capacity amounting to a savingof thousands of dollars may be achieved.

A primary object .of the invention is to provide a ratcheting open-endwrench having pivoted jaws and a handle pivoted to one of the jaws insuch a manner that a turning force. applied to the handle in onedirection tends to close the jaws regardless of how the turning forcemay be applied.

A further object of the invention is to provide in a wrench of the typedescribed an improved shape for the jaw teeth whereby ratcheting of thewrench is facilitated and slippage prevented.

A further object is to provide in'a wrench of the class described a'construction which limits the jaw opening'toprovid'e resilient openingfor insertion over a nut, and locking action in all tangential openingof the jaws with respect to each other takes place.

A further object is to provide a spring loaded thumb release for holdingthe jaws'of a ratcheting open-end wrench in. an open or ratchetingposition.

A further object is to provide a toggle clamping action in a ratchetingopen-end wrench.

A still further object is to provide lever actuating means for togglelocked jaws in a ratcheting open-end wrench.

Further objects will'be apparent from the specifications and drawings,in which:

Fig. 1 is a plan view of my open-end ratcheting wrench. having a pair ofnotched pivoting jawsand ahandle pivoted on one of the jaws;

.Fig. 2. is a. slightly enlarged detail of the jaws showing. thelocationof thepivot pins with respect to the jaw teeth and the method ofconstructing my wrench; andv Fig. 3 shows the structure of Fig. 2 withthe jaws in the open position.

I have found that extremely good results may be obtained in ratchetingopen-end wrench having pivoted notched jaws by placing the jaw pivotpins in such a: position that turning force exerted on the wrench handleis applied to' close the jaws so that no independent force to maintainthe jaws in this positionisnecessary. This result is achieved primarilythrough the shape of the jaws and the'location of the jaw teeth withrespect to the pivot points for. the jaws.

In an open-end wrench adapted to be used on hexagonal nuts, I havefound'that the maximum number of jaw teethwhich can be desirably.

used is four in each jaw. If more than this.

one jaw'and a nut or bolt head act asthe pivoting element and the otherjaw acts as the"lim'i iting element. Wrenches having somewhat sim ilaraction are described in my co-oending U. S.

Patent application Serial No. 68' .59l.

While certain novel features of the-inventionare disclosed hereinwithconsiderabledetailwitn respect to certain particular forms of theinvention,.it is not desired to be limited to such details since manychanges and modifications may be made, particularly with respect to theexact arrangement of the toggle members, without departure from thefunction of the invention in its broadest aspect.

Referring now more particularly to the drawings, upper jaw 5 has aforwardly extending curved portion 6 containing a plurality of groovesor notches l with curved sides 8 and an included angle of substantially120. In a preferred embodiment, jaw 5 has four of such notches, theoutermost notch 9, however, having only a partial side at 9. Theinnermost tooth II in jaw 5 is completely formed but no complete notchoccurs at 2 since the exterior face of jaw 5 is cut away at this point.Jaw 5 extends rearwardly and has a pair of bifurcations 13 formedintegrally with the jaw.

Lower jaw i i has a forward portion i5 carrying similar notches l andcurved teeth 8. In

the preferred form, lower jaw H3 has three" notches l and three fullyformed teeth 8', whereas a fourth and innermost tooth i6 is formed witha much smaller radius than teeth 8'. Jaw M has a thinned rearwardlyextending portion ll adapted to fit between bifurcations [3 of upper jaw5, and pinned thereto by means of pin i8. Recess [9 in the lower jawaccommodates helical spring 28 which abuts extension 2| of handle 22 andurges the lower jaw and the handle away from each other at this point.Handle 22 likewise has a thinned extension 23 adapted to be enclosedwithin bifurcations l3 and to be pivoted to the bifurcations by means ofpin 2t. In the operative position, handie 22 (as seen in Fig. 2) canpivot clockwise on pin 24 until it contacts lever arm ll of jaw H1 atpoint 25. This pivoting motion is accentuated by spring Zil.

Shown by broken lines is a hexagonal nut or bolt head 26, which appearsin two positions, the second of which is rotated 30 from the firstposition. For purposes of structure, the reference numeral 26 indicatesa nut, but the composite outline of the nut in alternate 30 positionsforms a 24-sided polygon with 120 interior angles at the points orcorners lettered A to L consecutively, and 150 exterior anglesalternately between the points (Fig. 2). The polygon A-L will bereferred to hereinafter for purposes of iocating and laying out theconstruction lines for notches I, l" and pins l8 and 2d.

The pivoting movement of jaw 14 on pin 18 is limited in one direction bya shoulder 21? on jaw l4, and an outer edge 28 of bifurcations IS. Theclearance between shoulder 2i and edge 28 is calculated so that a tightgrip on a standard size nut 26 is obtained several degrees beforeshoulder 2'! contacts edge 28. Pivoting action of jaw M in the oppositedirection is limited by contact with handle 22 at point in the closedposition, or with handle 22 at point 29 in the open position (Fig. 3).The total opening of jaw 1 is such that ample clearance between theouter tips of the jaws is provided for insertion of the nut or bolt head26. 7

As will more fully appear below, the relative length of portion 85 ofjaw IQ with respect to portion H is such that the distance between thecenter 39 of pin is and contact point 25 is greater than the distancefrom pin center 30 to any notch or tooth i or 8 on portion i5. Similarlythe distance between center 3i of pin 26 and point 25 is considerablyless than any point on handle 22 to which turning force may be appliedby an operai 4 tor. This construction provides a double mechanicaladvantage for actuating the jaws and consequently tight gripping of nut26. Tightening of the jaws is obtained by rotating the entire wrench ina clockwise direction in Fig. 2. This action causes extreme grippingaction on nut 26 due in part to the double mechanical advantage of thehandle with respect to jaw 15, and also to the toggle action whichtakesplace between the outer notches of jaw 5, particularly notch 9, innernotches of jaw I l and pin 18. It will be apparent that rotation of thewrench handle in a clockwise direction tends to rotate jaw l4 in aclockwise direction on pin l8. This provides a toggle gripping actionwhich in ordinary circumstances would be ample to securely grip nut 26without the additional expedient of pin 24 and rotatable handle 22.

In order that the foregoing toggle action oci cur, however, it isimportant that contact be made at all times between the teeth of bothjaws and nut 25. Spring 28 performs this function, since it also urgesjaw 14 to rotate in a clockwise direction on pin i8, regardless of theposition of handle 22. I have found that the curved configuration ofnotches l and l materially aids the ratcheting of the wrench which takesplace when handle 22 is turned in a counterclockwise direction. Thismovement causes the handle to pivot slightly on pin 24, thereby removingthe point of contact between handle 22 and extension i? to a point suchas 29, thus obtaining a limited opening clearance for jaw I 3 and jaw 5.The jaws may be held'in this open position by means of thumb pressure onextension I? in the event that it is desired to turn the wrench ineither direction without gripping nut 25. I have found that a desirableradius for teeth 8 and 8' is .172 inch for a nut having a width off/inch across its flats. It will be understood that the desired radius forthe teeth will vary in accordance with the particular size of the wrenchin question.

The construction and location of the pivot pins with respect to theteeth will now be explained. A 24-sided polygon, A, B, C, D, E, F, G, H,I, J, K, L, having a diameter corresponding to the size nut for whichthe wrench is to be designed, is first laid out. Assuming that thenotches 1 in upper jaw 5 will contact apexes A, B, C and D of thepolygon, it will be seen that this permits apex E to be unenclosed by afull notch in jaw 5, and apexes J, K and L to be entirely free from anycontact with either jaw. A construction line is then drawn to connectapex B, the second notch from the outer extremity of jaw 5, with apex F,the apex of the polygon which precedes the first notch from the innerextremity of jaw M. A similar construction line is drawn to connectpoint J and point H of the polygon, the latter apex being the apex ofthe polygon which coincides with the first full notch from the outerextremity of lower jaw I4. Lines BF and JH will intersect at point at,thereby locating the center of pin 18. Apexes K and F of the polygon arethen joined by construction line KB, and an arc, with the distance frompin center 39 to apex I of the polygon as a radius, is swung tointersect line KF at 3!, thus locating the center of pin 24. Thedesirable location for point 25 to insure that arm I? is longer than anycontact point of jaw 14 with the nut, is obtained by swinging an arc,with point 30 as the center and the distance from point 36 to apex J asa radius, to intersect a line connecting apexes L and F of the polygon.The identical procedure may be uti- Arranalysis of this constructionreveals that the. entire'nut is offset from the operative centerlin'e 32of handle 22, and that. the center ofipin i8 is slightly below, in Fig.2, a line connectingthe notch or u .or jaw 5 adjacent apex A-and the.notch in lower jaw i i adjacent apex This location of pin l8 insures a.toggle action of the jaws in clamping nut 28, regardless of which-3'0.degree position the nut .may assume in the teeth of the jaw.Furthermore, this location provides a minimum of relative jaw movementtoefiectuate suflicient clearance in the jaws for easyinsertion of a nut,as well at ratcheting. This feature is clearly shown in Fig. 3.

Itis contemplated that the construction of my wrench is. readily adaptedto various methods of manufacture,v since the jaws may be made bylaminated stampings, or iorgings, as desired, and the extremely highgripping power or" the wrench permits an. operator to obtain excellentresults in: close quarters with a relatively short wrench handle.

Having thus described my invention, I claim:

1. A ratcheting o en end wrench having a first jaw, a second jawpivotedto said first jaw, apivot pin for thefirstiand second jaws, and aplurality of notches in eachof said jaws adapted to grip a hexagonalelement; the pivot pin being located, wheniithe jaws have closed on saidhexagonal element, substantially at the intersection of a straightlinepassing through a first. and third apex: orthe hexagonal element, andstraight line passing through a fourth and fifth apex of the hexagonalelement; and in which the first apex-"of the hexagonalelernent isgripped by a second innermost notch on the upper jaw, and the fourthapex of the hexagonal element is grippedby an outermostnotch in thesecond jaw.

2. A ratcheting open end wrench having a first jaw, a second jaw pivotedto said first jaw, a pivotpin for the first and second jaws, and aplurality of notches in each of said jaws adapted to: grip a hexagonalelement; the pivot pin being located, when the jaws have closed on saidhexagonal element, substantially at the intersectionof a straight linepassing through a first and-third apex of the hexagonal element, and astraight line passing through a fourth and fifth apex of the hexagonalelement; and in which the-first jaw is provided with four notches andf'ourfullteeth, and the second jaw is provided with two-fullnotches andthree full teeth.

3. A ratcheting open end wrench having a first jaw, asecond jaw pivotedto said first jaw, a pivot pin for the first and second jaws, andaplurality of notches in each of said jaws adapted to grip ahexagonal'element; the pivot pin being located,..when the jaws haveclosed on said hexagonal element, substantially at the intersection of astraightline passing through a first and third apex of the hexagonalelement, and a straight line passing through a fourth and fifth apex ofthehexagonal element; and in which the first jawis providedwithfour fullnotches and four full'teeth, the'second jaw is provided with twofullnotches and two full teeth, and the first apex of the hexagonalelement is gripped by a second innermost notch'On the upper jaw and thefourth apex of the hexagonal element is gripped by an outermost notch inthe second jaw.

4. Aratcheting open end wrench havinga first jaw, asecond'jaw pivoted tosaid first jaw, a pivot pin'forthe-first and'second jaws, a plurality ofamaze-as:-

notchesinfeach .cf said jaws, said notches adapted tog-rip a hexagonal.element, a. handle pivoted: to; said firstajaw, and a pivot pinior saidhandleiandfirst jaw; the pivot-pin for. the jaws being; located,- whenthe-jawshave closed on said hexag-onalelement,. substantially at theintersection of a. straight line passing, through a first and thirdapex. oflthe. hexagonal element, anda straight line passing through afourth and fifth apexof the; hexagonal element, and the pivot pin forth'erhandle. beingv located at theintersection of: a straight linepassing through a third apex of thei:heXag0na1 element and the fifthapexofthe hexagonal element when said element is rotated 30 aboutitscenter in the direction of the apex numbers, and an arc. swung from theintersection of said jaw pivot pin locating lines and having; a radiussubstantially equal to the distance from said last named intersection tothe fourth apex of the hexagonal element when said hexagonal element isrotated 30 in the direction of the apex numbers.

5. Aratchetingvopen end wrench in accordance. with claim 4 in which thesecond jaw is provided with a leverv to abut the handle, the point of:abutment between the handle and the lever in closed jaw position beingspaced from the jaw pivot pin not less than the distance betweenthecenter of said jaw pivot pin and the fifthv apex of the hexagonalelement;-

6. A ratcheting open end wrench in accordance with claim 4 havingresilient means for urging the jaws into closed position.

'7. A ratcheting open end wren-chconstructed in accordance with claim 4in which the notches are formed between curved teeth in the jaws.

8. A ratcheting open end wrench constructed. in accordance with claim 4in which'the first apexof the hexagonal element is gripped by a. secondinnermost notch on the upper jaw, and the fourth apex of the hexagonalelement is gripped by an outermost notch in thesecond jaw.

9. A ratcheting open end wrench constructed in accordance with claim 4in which the first jaw is provided with four notches and four fullteeth,

and the second jaw is provided with two full notches and three fullteeth.

10. A ratcheting open end wrench constructed in accordance with claim 4in which the first jaw is provided with four full notches and four, fullteeth,vthe second jaw is provided with two full notches and two fullteeth, and the first apex of the hexagonal element is gripped by asecond innermost notch on the upper jaw and the fourth apex of thehexagonal element is gripped by an outermost notch in the second jaw.

11. A ratcheting open end wrench comprising afirst jaw having aplurality of curved teeth formin notches between said teeth, abifurcated extension on said jaw, a second jaw having; a plurality ofcurved teeth forming 120 notchesbetween said teeth, said notches andteeth being adapted to grip a hexagonal element, an extension on saidsecond jaw adapted to be enclosed within the bifurcations of the firstjaw, a pivot for the jaws extending through the bifurcations and thesecond jaw, a handle pivoted between the bifurcations of the first jawand abuttingthe extension. on the second jaw, and a pivot for saidhandle and first jaw; the pivot for the jawsbeing located when the jawshave closedon said hex-- agonal element, substantially at theintersection ofa straight line passing throughfirst and third apex ofthe hexagonal element and a straight line passingthrough a fourthand-fifthapexof the hexagonal element; and the handle pivot beinglocated at the intersection of: a straight line passing through a thirdapex of the hexagonal element and the fifth apex of the hexagonalelement when said element is rotated 30 about its center in thedirection of the apex numbers, and an arc swung from the jaw pivotcenter and having a radius not less than the distance between said jawpivot center and the fourth apex of the hexagonal element when saidelement is rotated 30 about its center in the direction of the apexnumbers.

12. A ratcheting open end wrench constructed in accordance with claim 11in which the first jaw is provided with four notches and four fullteeth, and the second jaw is provided with two full notches and threefull teeth.

13. A ratcheting open end wrench constructed in accordance with claim 11in which the first jaw is provided with four full notches and four fullteeth, the second jaw is provided with two full notches and two fullteeth, and the first apex of the hexagonal element is gripped by asecond innermost notch on the upper jaw and the fourth apex of thehexagonal element is gripped by an outermost notch in the second jaw.

14. In the design of a ratcheting open end wrench having a pair ofnotched pivoted jaws, the method of locating the relative positions ofthe jaw notches and pivot which comprises the steps of constructing anequilateral regular hexagon of the nut size for which the wrench isintended to be used, drawing a straight line between a first apex n thehexagon and a third consecutive apex on the hexagon, drawing a secondstraight line between the fourth consecutive apex on the hexagon and thefifth consecutive apex, extending said lines to intersect each other todetermine the center of the pivot point for the jaws, forming a notch inone of the jaws at the first and second apexes of the hexagon, formingnotches in said first jaw 30 on either side of said first apex, formingan intermediate notch in the second jaw at the third and fourth apexesof the hexagon, and forming a notch in the second jaw midway betweensaid third and fourth notches.

15. In the design of a ratcheting open end wrench having a pair ofnotched jaws pivoted to each other, a pivot for the jaws, and a handlepivoted to one of said jaws, the method of locating the relativepositions of said jaw notches, jaw pivot and handle pivot whichcomprises the steps of constructing an equilateral regular hexagon ofthe size'intended to be gripped by said jaws, locating the pivot centerfor the jaws substantially at the point of intersection between: astraight line connecting said first apex of the hexagon and the thirdapex of the hexagon, and a straight line connecting the fourth and fifthapexes of the hexagon, and locating the center of the pivot for thehandle and one of said jaws substantially at the intersection between: astraight line connecting the third apex of the hexagon and the fifthapex of the hexagon when the hexagon is rotated 30 about its center inthe direction of the apex numbers; and an arc swung from the jaw pivotcenter having a radius not less than the distance between said jaw pivotcenter and the fourth apex of the hexagonal element when said element isrotated 30 about its center in the direction of the apex numbers.

16. In the design of a ratchetin open end wrench having a pair ofnotched jaws pivoted to each other, a pivot for the jaws, a handlepivoted 8 to one of said jaws, and an abutment between one of the jawsand the handle, the method of locating the relative positions of saidjaw notches, jaw pivot, handle pivot, and abutment which comprises thesteps of constructing an equilateral regular hexagon of the sizeintended to be gripped by said jaws so that a first apex of the hexagoncoincides with the position of the second innermost notch on the firstjaw, locating the pivot center for the jaws substantially at the pointof intersection between: the line connecting said first apex of thehexagon and the third apex of the hexagon, and a line connecting thefourth and fifth apexes of the hexagon; a line connecting the fourth andfifth apexes of the hexagon, and locatin the center of the pivot for thehandle and one of said jaws substantially at the intersection between: aline connecting the third apex of the hexagon and the fifth apex of thehexagon when the hexagon is rotated 30 about its center in the directionof the apex numbers; and locating the point of abutment between one ofsaid jaws and the handle substantially at the intersection between: aline connecting the third and sixth apexes of the hexagon and an arehaving a radius not less than the distance between said center and thefifth apex of the hexagon.

17. The method of locatingthe relative position of the jaw notches withrespect to the jaw pivot in the upper jaw of a Wrench of the classdescribed which comprises the steps of claim 14, rotating the hexagon 30about its center in the direction of the apex numbers, locating theoutermost notch in the upper jaw in a position coinciding with the sixthapex of the hexagon in the rotated position, locating the secondinnermost notch in the upper jaw in a position coinciding with the firstapex of the hexagon in the original position, locating the thirdinnermost notch in the upper jaw in a position coinciding with the firstapex of the hexagon in the rotated position and locating the fourthnotch in the upper jaw in a position coinciding with the second apex ofthe hexagon in the original position.

18. The method of locating the relative position of a plurality of jawnotches in the lower with respect to the jaw pivot in a wrench oi theclass described which comprises the steps of claim 16, rotating thehexagon 30 about its center, locating the outermost notch in the lowerjaw in a position coinciding with the fourth notch of the hexagon in theoriginal position and locatlllg the second innermost notch on the lowerjaw in a position coinciding with the third apex of the hexagon in therotated position.

GEORGE T. LOGAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 486,764 Carpenter Nov. 22, 1892733,138 Bullard July 7, 1903 813,892 Hielscher et a1. Feb. 27, 19061,386,136 Sibbold Aug. 2, 1921 1,627,035 Jahn May 3, 1927 1,692,911Vaughn Nov. 27, 1928 FGREIGN PATENTS Number Country Date 21,530 GreatBritain Nov. 28, 1900 449,510 Germany Sept. 20, 1927

